This proposal is to systematically characterize the vasoactive components of arachidonate in the systemic, pulmonary and hind limb circulation. This will be done by a combined haemodynamic-pharmacological approach which includes use of prostanoate and non-prostanoate metabolites, arachidonate, prostaglandin antagonists and enzyme inhibitors. In this, we will possess a bank of haemodynamic data in a single species which we will then apply to study (1) venous compliance and (2) experimental congestive heart failure.